--- /dev/null
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+#include "runtime.h"
+#include "hashmap.h"
+
+/* Return a pointer to the struct/union of type "type"
+ whose "field" field is addressed by pointer "p". */
+
+struct hash { /* a hash table; initialize with hash_init() */
+ uint32 count; /* elements in table - must be first */
+
+ uint8 datasize; /* amount of data to store in entry */
+ uint8 max_power; /* max power of 2 to create sub-tables */
+ uint8 max_probes; /* max entries to probe before rehashing */
+ int32 changes; /* inc'ed whenever a subtable is created/grown */
+ hash_hash_t (*data_hash) (uint32, void *a); /* return hash of *a */
+ uint32 (*data_eq) (uint32, void *a, void *b); /* return whether *a == *b */
+ void (*data_del) (uint32, void *arg, void *data); /* invoked on deletion */
+ struct hash_subtable *st; /* first-level table */
+
+ uint32 keysize;
+ uint32 valsize;
+ uint32 ko;
+ uint32 vo;
+ uint32 po;
+ Alg* keyalg;
+ Alg* valalg;
+};
+
+struct hash_entry {
+ hash_hash_t hash; /* hash value of data */
+ byte data[1]; /* user data has "datasize" bytes */
+};
+
+struct hash_subtable {
+ uint8 power; /* bits used to index this table */
+ uint8 used; /* bits in hash used before reaching this table */
+ uint8 datasize; /* bytes of client data in an entry */
+ uint8 max_probes; /* max number of probes when searching */
+ int16 limit_bytes; /* max_probes * (datasize+sizeof (hash_hash_t)) */
+ struct hash_entry *end; /* points just past end of entry[] */
+ struct hash_entry entry[1]; /* 2**power+max_probes-1 elements of elemsize bytes */
+};
+
+#define HASH_DATA_EQ(h,x,y) ((*h->data_eq) (h->keysize, (x), (y)))
+
+#define HASH_REHASH 0x2 /* an internal flag */
+/* the number of bits used is stored in the flags word too */
+#define HASH_USED(x) ((x) >> 2)
+#define HASH_MAKE_USED(x) ((x) << 2)
+
+#define HASH_LOW 6
+#define HASH_ONE (((hash_hash_t)1) << HASH_LOW)
+#define HASH_MASK (HASH_ONE - 1)
+#define HASH_ADJUST(x) (((x) < HASH_ONE) << HASH_LOW)
+
+#define HASH_BITS (sizeof (hash_hash_t) * 8)
+
+#define HASH_SUBHASH HASH_MASK
+#define HASH_NIL 0
+#define HASH_NIL_MEMSET 0
+
+#define HASH_OFFSET(base, byte_offset) \
+ ((struct hash_entry *) (((byte *) (base)) + (byte_offset)))
+
+
+/* return a hash layer with 2**power empty entries */
+static struct hash_subtable *
+hash_subtable_new (struct hash *h, int32 power, int32 used)
+{
+ int32 elemsize = h->datasize + offsetof (struct hash_entry, data[0]);
+ int32 bytes = elemsize << power;
+ struct hash_subtable *st;
+ int32 limit_bytes = h->max_probes * elemsize;
+ int32 max_probes = h->max_probes;
+
+ if (bytes < limit_bytes) {
+ limit_bytes = bytes;
+ max_probes = 1 << power;
+ }
+ bytes += limit_bytes - elemsize;
+ st = malloc (offsetof (struct hash_subtable, entry[0]) + bytes);
+ st->power = power;
+ st->used = used;
+ st->datasize = h->datasize;
+ st->max_probes = max_probes;
+ st->limit_bytes = limit_bytes;
+ st->end = HASH_OFFSET (st->entry, bytes);
+ memset (st->entry, HASH_NIL_MEMSET, bytes);
+ return (st);
+}
+
+static void
+init_sizes (int64 hint, int32 *init_power, int32 *max_power)
+{
+ int32 log = 0;
+ int32 i;
+
+ for (i = 32; i != 0; i >>= 1) {
+ if ((hint >> (log + i)) != 0) {
+ log += i;
+ }
+ }
+ log += 1 + (((hint << 3) >> log) >= 11); /* round up for utilization */
+ if (log <= 14) {
+ *init_power = log;
+ } else {
+ *init_power = 12;
+ }
+ *max_power = 12;
+}
+
+static void
+hash_init (struct hash *h,
+ int32 datasize,
+ hash_hash_t (*data_hash) (uint32, void *),
+ uint32 (*data_eq) (uint32, void *, void *),
+ void (*data_del) (uint32, void *, void *),
+ int64 hint)
+{
+ int32 init_power;
+ int32 max_power;
+
+ if(datasize < sizeof (void *))
+ datasize = sizeof (void *);
+ init_sizes (hint, &init_power, &max_power);
+ h->datasize = datasize;
+ h->max_power = max_power;
+ h->max_probes = 15;
+ assert (h->datasize == datasize);
+ assert (h->max_power == max_power);
+ assert (sizeof (void *) <= h->datasize || h->max_power == 255);
+ h->count = 0;
+ h->changes = 0;
+ h->data_hash = data_hash;
+ h->data_eq = data_eq;
+ h->data_del = data_del;
+ h->st = hash_subtable_new (h, init_power, 0);
+}
+
+static void
+hash_remove_n (struct hash_subtable *st, struct hash_entry *dst_e, int32 n)
+{
+ int32 elemsize = st->datasize + offsetof (struct hash_entry, data[0]);
+ struct hash_entry *src_e = HASH_OFFSET (dst_e, n * elemsize);
+ struct hash_entry *end_e = st->end;
+ int32 shift = HASH_BITS - (st->power + st->used);
+ int32 index_mask = (((hash_hash_t)1) << st->power) - 1;
+ int32 dst_i = (((byte *) dst_e) - ((byte *) st->entry)) / elemsize;
+ int32 src_i = dst_i + n;
+ hash_hash_t hash;
+ int32 skip;
+ int32 bytes;
+
+ while (dst_e != src_e) {
+ if (src_e != end_e) {
+ struct hash_entry *cp_e = src_e;
+ int32 save_dst_i = dst_i;
+ while (cp_e != end_e && (hash = cp_e->hash) != HASH_NIL &&
+ ((hash >> shift) & index_mask) <= dst_i) {
+ cp_e = HASH_OFFSET (cp_e, elemsize);
+ dst_i++;
+ }
+ bytes = ((byte *) cp_e) - (byte *) src_e;
+ memmove (dst_e, src_e, bytes);
+ dst_e = HASH_OFFSET (dst_e, bytes);
+ src_e = cp_e;
+ src_i += dst_i - save_dst_i;
+ if (src_e != end_e && (hash = src_e->hash) != HASH_NIL) {
+ skip = ((hash >> shift) & index_mask) - dst_i;
+ } else {
+ skip = src_i - dst_i;
+ }
+ } else {
+ skip = src_i - dst_i;
+ }
+ bytes = skip * elemsize;
+ memset (dst_e, HASH_NIL_MEMSET, bytes);
+ dst_e = HASH_OFFSET (dst_e, bytes);
+ dst_i += skip;
+ }
+}
+
+static int32
+hash_insert_internal (struct hash_subtable **pst, int32 flags, hash_hash_t hash,
+ struct hash *h, void *data, void **pres);
+
+static void
+hash_conv (struct hash *h,
+ struct hash_subtable *st, int32 flags,
+ hash_hash_t hash,
+ struct hash_entry *e)
+{
+ int32 new_flags = (flags + HASH_MAKE_USED (st->power)) | HASH_REHASH;
+ int32 shift = HASH_BITS - HASH_USED (new_flags);
+ hash_hash_t prefix_mask = (-(hash_hash_t)1) << shift;
+ int32 elemsize = h->datasize + offsetof (struct hash_entry, data[0]);
+ void *dummy_result;
+ struct hash_entry *de;
+ int32 index_mask = (1 << st->power) - 1;
+ hash_hash_t e_hash;
+ struct hash_entry *pe = HASH_OFFSET (e, -elemsize);
+
+ while (e != st->entry && (e_hash = pe->hash) != HASH_NIL && (e_hash & HASH_MASK) != HASH_SUBHASH) {
+ e = pe;
+ pe = HASH_OFFSET (pe, -elemsize);
+ }
+
+ de = e;
+ while (e != st->end &&
+ (e_hash = e->hash) != HASH_NIL &&
+ (e_hash & HASH_MASK) != HASH_SUBHASH) {
+ struct hash_entry *target_e = HASH_OFFSET (st->entry, ((e_hash >> shift) & index_mask) * elemsize);
+ struct hash_entry *ne = HASH_OFFSET (e, elemsize);
+ hash_hash_t current = e_hash & prefix_mask;
+ if (de < target_e) {
+ memset (de, HASH_NIL_MEMSET, ((byte *) target_e) - (byte *) de);
+ de = target_e;
+ }
+ if ((hash & prefix_mask) == current ||
+ (ne != st->end && (e_hash = ne->hash) != HASH_NIL &&
+ (e_hash & prefix_mask) == current)) {
+ struct hash_subtable *new_st = hash_subtable_new (h, 1, HASH_USED (new_flags));
+ int32 rc = hash_insert_internal (&new_st, new_flags, e->hash, h, e->data, &dummy_result);
+ assert (rc == 0);
+ memcpy(dummy_result, e->data, h->datasize);
+ e = ne;
+ while (e != st->end && (e_hash = e->hash) != HASH_NIL && (e_hash & prefix_mask) == current) {
+ assert ((e_hash & HASH_MASK) != HASH_SUBHASH);
+ rc = hash_insert_internal (&new_st, new_flags, e_hash, h, e->data, &dummy_result);
+ assert (rc == 0);
+ memcpy(dummy_result, e->data, h->datasize);
+ e = HASH_OFFSET (e, elemsize);
+ }
+ memset (de->data, HASH_NIL_MEMSET, h->datasize);
+ *(struct hash_subtable **)de->data = new_st;
+ de->hash = current | HASH_SUBHASH;
+ } else {
+ if (e != de) {
+ memcpy (de, e, elemsize);
+ }
+ e = HASH_OFFSET (e, elemsize);
+ }
+ de = HASH_OFFSET (de, elemsize);
+ }
+ if (e != de) {
+ hash_remove_n (st, de, (((byte *) e) - (byte *) de) / elemsize);
+ }
+}
+
+static void
+hash_grow (struct hash *h, struct hash_subtable **pst, int32 flags)
+{
+ struct hash_subtable *old_st = *pst;
+ int32 elemsize = h->datasize + offsetof (struct hash_entry, data[0]);
+ *pst = hash_subtable_new (h, old_st->power + 1, HASH_USED (flags));
+ struct hash_entry *end_e = old_st->end;
+ struct hash_entry *e;
+ void *dummy_result;
+ int32 used = 0;
+
+ flags |= HASH_REHASH;
+ for (e = old_st->entry; e != end_e; e = HASH_OFFSET (e, elemsize)) {
+ hash_hash_t hash = e->hash;
+ if (hash != HASH_NIL) {
+ int32 rc = hash_insert_internal (pst, flags, e->hash, h, e->data, &dummy_result);
+ assert (rc == 0);
+ memcpy(dummy_result, e->data, h->datasize);
+ used++;
+ }
+ }
+ free (old_st);
+}
+
+int32
+hash_lookup (struct hash *h, void *data, void **pres)
+{
+ int32 elemsize = h->datasize + offsetof (struct hash_entry, data[0]);
+ hash_hash_t hash = (*h->data_hash) (h->keysize, data) & ~HASH_MASK;
+ struct hash_subtable *st = h->st;
+ int32 used = 0;
+ hash_hash_t e_hash;
+ struct hash_entry *e;
+ struct hash_entry *end_e;
+
+ hash += HASH_ADJUST (hash);
+ for (;;) {
+ int32 shift = HASH_BITS - (st->power + used);
+ int32 index_mask = (1 << st->power) - 1;
+ int32 i = (hash >> shift) & index_mask; /* i is the natural position of hash */
+
+ e = HASH_OFFSET (st->entry, i * elemsize); /* e points to element i */
+ e_hash = e->hash;
+ if ((e_hash & HASH_MASK) != HASH_SUBHASH) { /* a subtable */
+ break;
+ }
+ used += st->power;
+ st = *(struct hash_subtable **)e->data;
+ }
+ end_e = HASH_OFFSET (e, st->limit_bytes);
+ while (e != end_e && (e_hash = e->hash) != HASH_NIL && e_hash < hash) {
+ e = HASH_OFFSET (e, elemsize);
+ }
+ while (e != end_e && ((e_hash = e->hash) ^ hash) < HASH_SUBHASH) {
+ if (HASH_DATA_EQ (h, data, e->data)) { /* a match */
+ *pres = e->data;
+ return (1);
+ }
+ e = HASH_OFFSET (e, elemsize);
+ }
+ USED(e_hash);
+ *pres = 0;
+ return (0);
+}
+
+int32
+hash_remove (struct hash *h, void *data, void *arg)
+{
+ int32 elemsize = h->datasize + offsetof (struct hash_entry, data[0]);
+ hash_hash_t hash = (*h->data_hash) (h->keysize, data) & ~HASH_MASK;
+ struct hash_subtable *st = h->st;
+ int32 used = 0;
+ hash_hash_t e_hash;
+ struct hash_entry *e;
+ struct hash_entry *end_e;
+
+ hash += HASH_ADJUST (hash);
+ for (;;) {
+ int32 shift = HASH_BITS - (st->power + used);
+ int32 index_mask = (1 << st->power) - 1;
+ int32 i = (hash >> shift) & index_mask; /* i is the natural position of hash */
+
+ e = HASH_OFFSET (st->entry, i * elemsize); /* e points to element i */
+ e_hash = e->hash;
+ if ((e_hash & HASH_MASK) != HASH_SUBHASH) { /* a subtable */
+ break;
+ }
+ used += st->power;
+ st = *(struct hash_subtable **)e->data;
+ }
+ end_e = HASH_OFFSET (e, st->limit_bytes);
+ while (e != end_e && (e_hash = e->hash) != HASH_NIL && e_hash < hash) {
+ e = HASH_OFFSET (e, elemsize);
+ }
+ while (e != end_e && ((e_hash = e->hash) ^ hash) < HASH_SUBHASH) {
+ if (HASH_DATA_EQ (h, data, e->data)) { /* a match */
+ (*h->data_del) (h->keysize, arg, e->data);
+ hash_remove_n (st, e, 1);
+ h->count--;
+ return (1);
+ }
+ e = HASH_OFFSET (e, elemsize);
+ }
+ USED(e_hash);
+ return (0);
+}
+
+static int32
+hash_insert_internal (struct hash_subtable **pst, int32 flags, hash_hash_t hash,
+ struct hash *h, void *data, void **pres)
+{
+ int32 elemsize = h->datasize + offsetof (struct hash_entry, data[0]);
+
+ if ((flags & HASH_REHASH) == 0) {
+ hash += HASH_ADJUST (hash);
+ hash &= ~HASH_MASK;
+ }
+ for (;;) {
+ struct hash_subtable *st = *pst;
+ int32 shift = HASH_BITS - (st->power + HASH_USED (flags));
+ int32 index_mask = (1 << st->power) - 1;
+ int32 i = (hash >> shift) & index_mask; /* i is the natural position of hash */
+ struct hash_entry *start_e =
+ HASH_OFFSET (st->entry, i * elemsize); /* start_e is the pointer to element i */
+ struct hash_entry *e = start_e; /* e is going to range over [start_e, end_e) */
+ struct hash_entry *end_e;
+ hash_hash_t e_hash = e->hash;
+
+ if ((e_hash & HASH_MASK) == HASH_SUBHASH) { /* a subtable */
+ pst = (struct hash_subtable **) e->data;
+ flags += HASH_MAKE_USED (st->power);
+ continue;
+ }
+ end_e = HASH_OFFSET (start_e, st->limit_bytes);
+ while (e != end_e && (e_hash = e->hash) != HASH_NIL && e_hash < hash) {
+ e = HASH_OFFSET (e, elemsize);
+ i++;
+ }
+ if (e != end_e && e_hash != HASH_NIL) {
+ /* ins_e ranges over the elements that may match */
+ struct hash_entry *ins_e = e;
+ int32 ins_i = i;
+ hash_hash_t ins_e_hash;
+ while (ins_e != end_e && ((e_hash = ins_e->hash) ^ hash) < HASH_SUBHASH) {
+ if (HASH_DATA_EQ (h, data, ins_e->data)) { /* a match */
+ *pres = ins_e->data;
+ return (1);
+ }
+ assert (e_hash != hash || (flags & HASH_REHASH) == 0);
+ hash += (e_hash == hash); /* adjust hash if it collides */
+ ins_e = HASH_OFFSET (ins_e, elemsize);
+ ins_i++;
+ if (e_hash <= hash) { /* set e to insertion point */
+ e = ins_e;
+ i = ins_i;
+ }
+ }
+ /* set ins_e to the insertion point for the new element */
+ ins_e = e;
+ ins_i = i;
+ ins_e_hash = 0;
+ /* move ins_e to point at the end of the contiguous block, but
+ stop if any element can't be moved by one up */
+ while (ins_e != st->end && (ins_e_hash = ins_e->hash) != HASH_NIL &&
+ ins_i + 1 - ((ins_e_hash >> shift) & index_mask) < st->max_probes &&
+ (ins_e_hash & HASH_MASK) != HASH_SUBHASH) {
+ ins_e = HASH_OFFSET (ins_e, elemsize);
+ ins_i++;
+ }
+ if (e == end_e || ins_e == st->end || ins_e_hash != HASH_NIL) {
+ e = end_e; /* can't insert; must grow or convert to subtable */
+ } else { /* make space for element */
+ memmove (HASH_OFFSET (e, elemsize), e, ((byte *) ins_e) - (byte *) e);
+ }
+ }
+ if (e != end_e) {
+ e->hash = hash;
+ *pres = e->data;
+ return (0);
+ }
+ h->changes++;
+ if (st->power < h->max_power) {
+ hash_grow (h, pst, flags);
+ } else {
+ hash_conv (h, st, flags, hash, start_e);
+ }
+ }
+}
+
+int32
+hash_insert (struct hash *h, void *data, void **pres)
+{
+ int32 rc = hash_insert_internal (&h->st, 0, (*h->data_hash) (h->keysize, data), h, data, pres);
+
+ h->count += (rc == 0); /* increment count if element didn't previously exist */
+ return (rc);
+}
+
+uint32
+hash_count (struct hash *h)
+{
+ return (h->count);
+}
+
+static void
+iter_restart (struct hash_iter *it, struct hash_subtable *st, int32 used)
+{
+ int32 elemsize = it->elemsize;
+ hash_hash_t last_hash = it->last_hash;
+ struct hash_entry *e;
+ hash_hash_t e_hash;
+ struct hash_iter_sub *sub = &it->subtable_state[it->i];
+ struct hash_entry *end;
+
+ for (;;) {
+ int32 shift = HASH_BITS - (st->power + used);
+ int32 index_mask = (1 << st->power) - 1;
+ int32 i = (last_hash >> shift) & index_mask;
+
+ end = st->end;
+ e = HASH_OFFSET (st->entry, i * elemsize);
+ sub->start = st->entry;
+ sub->end = end;
+
+ if ((e->hash & HASH_MASK) != HASH_SUBHASH) {
+ break;
+ }
+ sub->e = HASH_OFFSET (e, elemsize);
+ sub = &it->subtable_state[++(it->i)];
+ used += st->power;
+ st = *(struct hash_subtable **)e->data;
+ }
+ while (e != end && ((e_hash = e->hash) == HASH_NIL || e_hash <= last_hash)) {
+ e = HASH_OFFSET (e, elemsize);
+ }
+ sub->e = e;
+}
+
+void *
+hash_next (struct hash_iter *it)
+{
+ int32 elemsize = it->elemsize;
+ struct hash_iter_sub *sub = &it->subtable_state[it->i];
+ struct hash_entry *e = sub->e;
+ struct hash_entry *end = sub->end;
+ hash_hash_t e_hash = 0;
+
+ if (it->changes != it->h->changes) { /* hash table's structure changed; recompute */
+ it->changes = it->h->changes;
+ it->i = 0;
+ iter_restart (it, it->h->st, 0);
+ sub = &it->subtable_state[it->i];
+ e = sub->e;
+ end = sub->end;
+ }
+ if (e != sub->start && it->last_hash != HASH_OFFSET (e, -elemsize)->hash) {
+ struct hash_entry *start = HASH_OFFSET (e, -(elemsize * it->h->max_probes));
+ struct hash_entry *pe = HASH_OFFSET (e, -elemsize);
+ hash_hash_t last_hash = it->last_hash;
+ if (start < sub->start) {
+ start = sub->start;
+ }
+ while (e != start && ((e_hash = pe->hash) == HASH_NIL || last_hash < e_hash)) {
+ e = pe;
+ pe = HASH_OFFSET (pe, -elemsize);
+ }
+ while (e != end && ((e_hash = e->hash) == HASH_NIL || e_hash <= last_hash)) {
+ e = HASH_OFFSET (e, elemsize);
+ }
+ }
+
+ for (;;) {
+ while (e != end && (e_hash = e->hash) == HASH_NIL) {
+ e = HASH_OFFSET (e, elemsize);
+ }
+ if (e == end) {
+ if (it->i == 0) {
+ it->last_hash = HASH_OFFSET (e, -elemsize)->hash;
+ sub->e = e;
+ return (0);
+ } else {
+ it->i--;
+ sub = &it->subtable_state[it->i];
+ e = sub->e;
+ end = sub->end;
+ }
+ } else if ((e_hash & HASH_MASK) != HASH_SUBHASH) {
+ it->last_hash = e->hash;
+ sub->e = HASH_OFFSET (e, elemsize);
+ return (e->data);
+ } else {
+ struct hash_subtable *st =
+ *(struct hash_subtable **)e->data;
+ sub->e = HASH_OFFSET (e, elemsize);
+ it->i++;
+ assert (it->i < sizeof (it->subtable_state) /
+ sizeof (it->subtable_state[0]));
+ sub = &it->subtable_state[it->i];
+ sub->e = e = st->entry;
+ sub->start = st->entry;
+ sub->end = end = st->end;
+ }
+ }
+}
+
+void
+hash_iter_init (struct hash *h, struct hash_iter *it)
+{
+ it->elemsize = h->datasize + offsetof (struct hash_entry, data[0]);
+ it->changes = h->changes;
+ it->i = 0;
+ it->h = h;
+ it->last_hash = 0;
+ it->subtable_state[0].e = h->st->entry;
+ it->subtable_state[0].start = h->st->entry;
+ it->subtable_state[0].end = h->st->end;
+}
+
+static void
+clean_st (struct hash_subtable *st, int32 *slots, int32 *used)
+{
+ int32 elemsize = st->datasize + offsetof (struct hash_entry, data[0]);
+ struct hash_entry *e = st->entry;
+ struct hash_entry *end = st->end;
+ int32 lslots = (((byte *) end) - (byte *) e) / elemsize;
+ int32 lused = 0;
+
+ while (e != end) {
+ hash_hash_t hash = e->hash;
+ if ((hash & HASH_MASK) == HASH_SUBHASH) {
+ clean_st (*(struct hash_subtable **)e->data, slots, used);
+ } else {
+ lused += (hash != HASH_NIL);
+ }
+ e = HASH_OFFSET (e, elemsize);
+ }
+ free (st);
+ *slots += lslots;
+ *used += lused;
+}
+
+void
+hash_destroy (struct hash *h)
+{
+ int32 slots = 0;
+ int32 used = 0;
+
+ clean_st (h->st, &slots, &used);
+ free (h);
+}
+
+static void
+hash_visit_internal (struct hash_subtable *st,
+ int32 used, int32 level,
+ void (*data_visit) (void *arg, int32 level, void *data),
+ void *arg)
+{
+ int32 elemsize = st->datasize + offsetof (struct hash_entry, data[0]);
+ struct hash_entry *e = st->entry;
+ int32 shift = HASH_BITS - (used + st->power);
+ int32 i = 0;
+
+ while (e != st->end) {
+ int32 index = ((e->hash >> (shift - 1)) >> 1) & ((1 << st->power) - 1);
+ if ((e->hash & HASH_MASK) == HASH_SUBHASH) {
+ (*data_visit) (arg, level, e->data);
+ hash_visit_internal (*(struct hash_subtable **)e->data,
+ used + st->power, level + 1, data_visit, arg);
+ } else {
+ (*data_visit) (arg, level, e->data);
+ }
+ if (e->hash != HASH_NIL) {
+ assert (i < index + st->max_probes);
+ assert (index <= i);
+ }
+ e = HASH_OFFSET (e, elemsize);
+ i++;
+ }
+}
+
+void
+hash_visit (struct hash *h, void (*data_visit) (void *arg, int32 level, void *data), void *arg)
+{
+ hash_visit_internal (h->st, 0, 0, data_visit, arg);
+}
+
+//
+/// interfaces to go runtime
+//
+
+static void
+donothing(uint32 s, void *a, void *b)
+{
+ USED(s);
+ USED(a);
+ USED(b);
+}
+
+typedef struct hash Hmap;
+static int32 debug = 0;
+
+// newmap(keysize uint32, valsize uint32,
+// keyalg uint32, valalg uint32,
+// hint uint32) (hmap *map[any]any);
+void
+sys·newmap(uint32 keysize, uint32 valsize,
+ uint32 keyalg, uint32 valalg, uint32 hint,
+ Hmap* ret)
+{
+ Hmap *h;
+
+ if(keyalg >= 3 ||
+ valalg >= 3) {
+ prints("0<=");
+ sys·printint(keyalg);
+ prints("<");
+ sys·printint(nelem(algarray));
+ prints("\n0<=");
+ sys·printint(valalg);
+ prints("<");
+ sys·printint(nelem(algarray));
+ prints("\n");
+
+ throw("sys·newmap: key/val algorithm out of range");
+ }
+
+ h = mal(sizeof(*h));
+ hash_init(h, keysize+valsize,
+ algarray[keyalg].hash,
+ algarray[keyalg].equal,
+ donothing,
+ hint);
+
+ h->keysize = keysize;
+ h->valsize = valsize;
+ h->keyalg = &algarray[keyalg];
+ h->valalg = &algarray[valalg];
+
+ // these calculations are compiler dependent
+ h->ko = rnd(sizeof(h), keysize);
+ h->vo = rnd(h->ko+keysize, valsize);
+ h->po = rnd(h->vo+valsize, 1);
+
+ ret = h;
+ FLUSH(&ret);
+
+ if(debug) {
+ prints("newmap: map=");
+ sys·printpointer(h);
+ prints("; keysize=");
+ sys·printint(keysize);
+ prints("; valsize=");
+ sys·printint(valsize);
+ prints("; keyalg=");
+ sys·printint(keyalg);
+ prints("; valalg=");
+ sys·printint(valalg);
+ prints("; ko=");
+ sys·printint(h->ko);
+ prints("; vo=");
+ sys·printint(h->vo);
+ prints("; po=");
+ sys·printint(h->po);
+ prints("\n");
+ }
+}
+
+// mapaccess1(hmap *map[any]any, key any) (val any);
+void
+sys·mapaccess1(Hmap *h, ...)
+{
+ byte *ak, *av;
+ byte *res;
+ int32 hit;
+
+ ak = (byte*)&h + h->ko;
+ av = (byte*)&h + h->vo;
+
+ res = nil;
+ hit = hash_lookup(h, ak, (void**)&res);
+ if(!hit)
+ throw("sys·mapaccess1: key not in map");
+ h->valalg->copy(h->valsize, av, res+h->keysize);
+
+ if(debug) {
+ prints("sys·mapaccess1: map=");
+ sys·printpointer(h);
+ prints("; key=");
+ h->keyalg->print(h->keysize, ak);
+ prints("; val=");
+ h->valalg->print(h->valsize, av);
+ prints("; hit=");
+ sys·printint(hit);
+ prints("; res=");
+ sys·printpointer(res);
+ prints("\n");
+ }
+}
+
+// mapaccess2(hmap *map[any]any, key any) (val any, pres bool);
+void
+sys·mapaccess2(Hmap *h, ...)
+{
+ byte *ak, *av, *ap;
+ byte *res;
+ int32 hit;
+
+ ak = (byte*)&h + h->ko;
+ av = (byte*)&h + h->vo;
+ ap = (byte*)&h + h->po;
+
+ res = nil;
+ hit = hash_lookup(h, ak, (void**)&res);
+ if(!hit) {
+ *ap = false;
+ h->valalg->copy(h->valsize, av, nil);
+ } else {
+ *ap = true;
+ h->valalg->copy(h->valsize, av, res+h->keysize);
+ }
+
+ if(debug) {
+ prints("sys·mapaccess2: map=");
+ sys·printpointer(h);
+ prints("; key=");
+ h->keyalg->print(h->keysize, ak);
+ prints("; val=");
+ h->valalg->print(h->valsize, av);
+ prints("; hit=");
+ sys·printint(hit);
+ prints("; res=");
+ sys·printpointer(res);
+ prints("; pres=");
+ sys·printbool(*ap);
+ prints("\n");
+ }
+}
+
+static void
+mapassign(Hmap *h, byte *ak, byte *av)
+{
+ byte *res;
+ int32 hit;
+
+ res = nil;
+ hit = hash_insert(h, ak, (void**)&res);
+ h->keyalg->copy(h->keysize, res, ak);
+ h->valalg->copy(h->valsize, res+h->keysize, av);
+
+ if(debug) {
+ prints("mapassign: map=");
+ sys·printpointer(h);
+ prints("; key=");
+ h->keyalg->print(h->keysize, ak);
+ prints("; val=");
+ h->valalg->print(h->valsize, av);
+ prints("; hit=");
+ sys·printint(hit);
+ prints("; res=");
+ sys·printpointer(res);
+ prints("\n");
+ }
+}
+
+// mapassign1(hmap *map[any]any, key any, val any);
+void
+sys·mapassign1(Hmap *h, ...)
+{
+ byte *ak, *av;
+
+ ak = (byte*)&h + h->ko;
+ av = (byte*)&h + h->vo;
+
+ mapassign(h, ak, av);
+}
+
+// mapassign2(hmap *map[any]any, key any, val any, pres bool);
+void
+sys·mapassign2(Hmap *h, ...)
+{
+ byte *ak, *av, *ap;
+ byte *res;
+ int32 hit;
+
+ ak = (byte*)&h + h->ko;
+ av = (byte*)&h + h->vo;
+ ap = (byte*)&h + h->po;
+
+ if(*ap == true) {
+ // assign
+ mapassign(h, ak, av);
+ return;
+ }
+
+ // delete
+ hit = hash_remove(h, ak, (void**)&res);
+
+ if(debug) {
+ prints("mapassign2: map=");
+ sys·printpointer(h);
+ prints("; key=");
+ h->keyalg->print(h->keysize, ak);
+ prints("; hit=");
+ sys·printint(hit);
+ prints("; res=");
+ sys·printpointer(res);
+ prints("\n");
+ }
+}
--- /dev/null
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+
+/* A hash table.
+ Example, hashing nul-terminated char*s:
+ hash_hash_t str_hash (void *v) {
+ char *s;
+ hash_hash_t hash = 0;
+ for (s = *(char **)v; *s != 0; s++) {
+ hash = (hash ^ *s) * 2654435769U;
+ }
+ return (hash);
+ }
+ int str_eq (void *a, void *b) {
+ return (strcmp (*(char **)a, *(char **)b) == 0);
+ }
+ void str_del (void *arg, void *data) {
+ *(char **)arg = *(char **)data;
+ }
+
+ struct hash *h = hash_new (sizeof (char *), &str_hash, &str_eq, &str_del, 3, 12, 15);
+ ... 3=> 2**3 entries initial size
+ ... 12=> 2**12 entries before sprouting sub-tables
+ ... 15=> number of adjacent probes to attempt before growing
+
+ Example lookup:
+ char *key = "foobar";
+ char **result_ptr;
+ if (hash_lookup (h, &key, (void **) &result_ptr)) {
+ printf ("found in table: %s\n", *result_ptr);
+ } else {
+ printf ("not found in table\n");
+ }
+
+ Example insertion:
+ char *key = strdup ("foobar");
+ char **result_ptr;
+ if (hash_lookup (h, &key, (void **) &result_ptr)) {
+ printf ("found in table: %s\n", *result_ptr);
+ printf ("to overwrite, do *result_ptr = key\n");
+ } else {
+ printf ("not found in table; inserted as %s\n", *result_ptr);
+ assert (*result_ptr == key);
+ }
+
+ Example deletion:
+ char *key = "foobar";
+ char *result;
+ if (hash_remove (h, &key, &result)) {
+ printf ("key found and deleted from table\n");
+ printf ("called str_del (&result, data) to copy data to result: %s\n", result);
+ } else {
+ printf ("not found in table\n");
+ }
+
+ Example iteration over the elements of *h:
+ char **data;
+ struct hash_iter it;
+ hash_iter_init (h, &it);
+ for (data = hash_next (&it); data != 0; data = hash_next (&it)) {
+ printf ("%s\n", *data);
+ }
+ */
+
+#define malloc mal
+#define free(a) USED(a)
+#define offsetof(s,m) (uint32)(&(((s*)0)->m))
+#define memset(a,b,c) sys·memclr((byte*)(a), (uint32)(c))
+#define memmove(a,b,c) mmov((byte*)(a),(byte*)(b),(uint32)(c))
+#define memcpy(a,b,c) mcpy((byte*)(a),(byte*)(b),(uint32)(c))
+#define assert(a) if(!(a)) throw("assert")
+
+struct hash; /* opaque */
+struct hash_subtable; /* opaque */
+struct hash_entry; /* opaque */
+
+typedef uint64 uintptr_t;
+typedef uintptr_t hash_hash_t;
+
+struct hash_iter {
+ int32 elemsize; /* size of elements in table */
+ int32 changes; /* number of changes observed last time */
+ int32 i; /* stack pointer in subtable_state */
+ hash_hash_t last_hash; /* last hash value returned */
+ struct hash *h; /* the hash table */
+ struct hash_iter_sub {
+ struct hash_entry *e; /* pointer into subtable */
+ struct hash_entry *start; /* start of subtable */
+ struct hash_entry *end; /* end of subtable */
+ } subtable_state[16]; /* Should be large enough unless the hashing is
+ so bad that many distinct data values hash
+ to the same hash value. */
+};
+
+/* Return a hashtable h 2**init_power empty entries, each with
+ "datasize" data bytes.
+ (*data_hash)(a) should return the hash value of data element *a.
+ (*data_eq)(a,b) should return whether the data at "a" and the data at "b"
+ are equal.
+ (*data_del)(arg, a) will be invoked when data element *a is about to be removed
+ from the table. "arg" is the argument passed to "hash_remove()".
+
+ Growing is accomplished by resizing if the current tables size is less than
+ a threshold, and by adding subtables otherwise. hint should be set
+ the expected maximum size of the table.
+ "datasize" should be in [sizeof (void*), ..., 255]. If you need a
+ bigger "datasize", store a pointer to another piece of memory. */
+
+//struct hash *hash_new (int32 datasize,
+// hash_hash_t (*data_hash) (void *),
+// int32 (*data_eq) (void *, void *),
+// void (*data_del) (void *, void *),
+// int64 hint);
+
+/* Lookup *data in *h. If the data is found, return 1 and place a pointer to
+ the found element in *pres. Otherwise return 0 and place 0 in *pres. */
+int32 hash_lookup (struct hash *h, void *data, void **pres);
+
+/* Lookup *data in *h. If the data is found, execute (*data_del) (arg, p)
+ where p points to the data in the table, then remove it from *h and return
+ 1. Otherwise return 0. */
+int32 hash_remove (struct hash *h, void *data, void *arg);
+
+/* Lookup *data in *h. If the data is found, return 1, and place a pointer
+ to the found element in *pres. Otherwise, return 0, allocate a region
+ for the data to be inserted, and place a pointer to the inserted element
+ in *pres; it is the caller's responsibility to copy the data to be
+ inserted to the pointer returned in *pres in this case.
+
+ If using garbage collection, it is the caller's responsibility to
+ add references for **pres if HASH_ADDED is returned. */
+int32 hash_insert (struct hash *h, void *data, void **pres);
+
+/* Return the number of elements in the table. */
+uint32 hash_count (struct hash *h);
+
+/* The following call is useful only if not using garbage collection on the
+ table.
+ Remove all sub-tables associated with *h.
+ This undoes the effects of hash_init().
+ If other memory pointed to by user data must be freed, the caller is
+ responsible for doiing do by iterating over *h first; see
+ hash_iter_init()/hash_next(). */
+void hash_destroy (struct hash *h);
+
+/*----- iteration -----*/
+
+/* Initialize *it from *h. */
+void hash_iter_init (struct hash *h, struct hash_iter *it);
+
+/* Return the next used entry in the table which which *it was initialized. */
+void *hash_next (struct hash_iter *it);
+
+/*---- test interface ----*/
+/* Call (*data_visit) (arg, level, data) for every data entry in the table,
+ whether used or not. "level" is the subtable level, 0 means first level. */
+/* TESTING ONLY: DO NOT USE THIS ROUTINE IN NORMAL CODE */
+void hash_visit (struct hash *h, void (*data_visit) (void *arg, int32 level, void *data), void *arg);
+++ /dev/null
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-#include "runtime.h"
-
-static int32 debug = 0;
-
-typedef struct Link Link;
-typedef struct Hmap Hmap;
-
-struct Link
-{
- Link* link;
- byte data[8];
-};
-
-struct Hmap
-{
- uint32 len; // must be first
- uint32 keysize;
- uint32 valsize;
- uint32 hint;
- uint32 valoffset;
- uint32 ko;
- uint32 vo;
- uint32 po;
- Alg* keyalg;
- Alg* valalg;
- Link* link;
-};
-
-// newmap(keysize uint32, valsize uint32,
-// keyalg uint32, valalg uint32,
-// hint uint32) (hmap *map[any]any);
-void
-sys·newmap(uint32 keysize, uint32 valsize,
- uint32 keyalg, uint32 valalg, uint32 hint,
- Hmap* ret)
-{
- Hmap *m;
-
- if(keyalg >= 3 ||
- valalg >= 3) {
- prints("0<=");
- sys·printint(keyalg);
- prints("<");
- sys·printint(nelem(algarray));
- prints("\n0<=");
- sys·printint(valalg);
- prints("<");
- sys·printint(nelem(algarray));
- prints("\n");
-
- throw("sys·newmap: key/val algorithm out of range");
- }
-
- m = mal(sizeof(*m));
-
- m->len = 0;
- m->keysize = keysize;
- m->valsize = valsize;
- m->keyalg = &algarray[keyalg];
- m->valalg = &algarray[valalg];
- m->hint = hint;
-
- // these calculations are compiler dependent
- m->valoffset = rnd(keysize, valsize);
- m->ko = rnd(sizeof(m), keysize);
- m->vo = rnd(m->ko+keysize, valsize);
- m->po = rnd(m->vo+valsize, 1);
-
- ret = m;
- FLUSH(&ret);
-
- if(debug) {
- prints("newmap: map=");
- sys·printpointer(m);
- prints("; keysize=");
- sys·printint(keysize);
- prints("; valsize=");
- sys·printint(valsize);
- prints("; keyalg=");
- sys·printint(keyalg);
- prints("; valalg=");
- sys·printint(valalg);
- prints("; valoffset=");
- sys·printint(m->valoffset);
- prints("; ko=");
- sys·printint(m->ko);
- prints("; vo=");
- sys·printint(m->vo);
- prints("; po=");
- sys·printint(m->po);
- prints("\n");
- }
-}
-
-// mapaccess1(hmap *map[any]any, key any) (val any);
-void
-sys·mapaccess1(Hmap *m, ...)
-{
- Link *l;
- byte *ak, *av;
-
- ak = (byte*)&m + m->ko;
- av = (byte*)&m + m->vo;
-
- for(l=m->link; l!=nil; l=l->link) {
- if(m->keyalg->equal(m->keysize, ak, l->data)) {
- m->valalg->copy(m->valsize, av, l->data+m->valoffset);
- goto out;
- }
- }
-
- m->valalg->copy(m->valsize, av, 0);
- throw("sys·mapaccess1: key not in map");
-
-out:
- if(debug) {
- prints("sys·mapaccess1: map=");
- sys·printpointer(m);
- prints("; key=");
- m->keyalg->print(m->keysize, ak);
- prints("; val=");
- m->valalg->print(m->valsize, av);
- prints("\n");
- }
-}
-
-// mapaccess2(hmap *map[any]any, key any) (val any, pres bool);
-void
-sys·mapaccess2(Hmap *m, ...)
-{
- Link *l;
- byte *ak, *av, *ap;
-
- ak = (byte*)&m + m->ko;
- av = (byte*)&m + m->vo;
- ap = (byte*)&m + m->po;
-
- for(l=m->link; l!=nil; l=l->link) {
- if(m->keyalg->equal(m->keysize, ak, l->data)) {
- *ap = true;
- m->valalg->copy(m->valsize, av, l->data+m->valoffset);
- goto out;
- }
- }
-
- *ap = false;
- m->valalg->copy(m->valsize, av, nil);
-
-out:
- if(debug) {
- prints("sys·mapaccess2: map=");
- sys·printpointer(m);
- prints("; key=");
- m->keyalg->print(m->keysize, ak);
- prints("; val=");
- m->valalg->print(m->valsize, av);
- prints("; pres=");
- sys·printbool(*ap);
- prints("\n");
- }
-}
-
-static void
-sys·mapassign(Hmap *m, byte *ak, byte *av)
-{
- Link *l;
-
- // mapassign(hmap *map[any]any, key any, val any);
-
- for(l=m->link; l!=nil; l=l->link) {
- if(m->keyalg->equal(m->keysize, ak, l->data))
- goto out;
- }
-
- l = mal((sizeof(*l)-8) + m->keysize + m->valsize);
- l->link = m->link;
- m->link = l;
- m->keyalg->copy(m->keysize, l->data, ak);
- m->len++;
-
-out:
- m->valalg->copy(m->valsize, l->data+m->valoffset, av);
-
- if(debug) {
- prints("mapassign: map=");
- sys·printpointer(m);
- prints("; key=");
- m->keyalg->print(m->keysize, ak);
- prints("; val=");
- m->valalg->print(m->valsize, av);
- prints("\n");
- }
-}
-
-// mapassign1(hmap *map[any]any, key any, val any);
-void
-sys·mapassign1(Hmap *m, ...)
-{
- byte *ak, *av;
-
- ak = (byte*)&m + m->ko;
- av = (byte*)&m + m->vo;
-
- sys·mapassign(m, ak, av);
-}
-
-// mapassign2(hmap *map[any]any, key any, val any, pres bool);
-void
-sys·mapassign2(Hmap *m, ...)
-{
- Link **ll;
- byte *ak, *av, *ap;
-
- ak = (byte*)&m + m->ko;
- av = (byte*)&m + m->vo;
- ap = (byte*)&m + m->po;
-
- if(*ap == true) {
- // assign
- sys·mapassign(m, ak, av);
- return;
- }
-
- // delete
- for(ll=&m->link; (*ll)!=nil; ll=&(*ll)->link) {
- if(m->keyalg->equal(m->keysize, ak, (*ll)->data)) {
- m->valalg->copy(m->valsize, (*ll)->data+m->valoffset, nil);
- (*ll) = (*ll)->link;
- m->len--;
- if(debug) {
- prints("mapdelete (found): map=");
- sys·printpointer(m);
- prints("; key=");
- m->keyalg->print(m->keysize, ak);
- prints("\n");
- }
- return;
- }
- }
-
- if(debug) {
- prints("mapdelete (not found): map=");
- sys·printpointer(m);
- prints("; key=");
- m->keyalg->print(m->keysize, ak);
- prints(" *** not found\n");
- }
-}